The term "stabilized chlorine dioxide" (Kick-Othmer Encyclopedia of Chemical Technology, Forth Ed., Vol. 5 1993, Chlorine Oxygen Acids and Salts, Kaczur, J. and Cawlfield, D. Editors, p.191. John Wiley & Sons, Inc) (SCD) is actually a misnomer, for there is nothing stable about molecular chlorine dioxide (ClO2). SCD is actually a solution of sodium chlorite (NaClO2) which has a peroxy compound added which reduces ClO2back to NaClO2, whereby a stabilized source for ClO2is achieved. Depending on the concentration of NaClO2, some ClO2is present. For example a 2000 mg/L concentration would have much less than 2 mg/L of CLO2--there is some but very little. SCD can quickly form significant amounts of ClO2, but only upon acidification with say a protic acid at very low pHs. (SCD) really has no chemical meaning. In practice SCD is synonymous with a solution that contains sodium chlorite buffered to a pH usually greater than pH 8. If the pH of a sodium chlorite solution becomes acidic, chlorine dioxide will be generated. Thus, the term stabilized chlorine dioxide refers to a buffered sodium chlorite solution.